Final answer:
Sergio, who is working on goal theory, is most likely researching what makes hospital workers motivated to work harder, as it aligns with how goals influence behaviors and is applicable in organizational psychology and human factors psychology.
Step-by-step explanation:
Sergio, as a psychologist working on goal theory, is likely to research topics that involve understanding how specific goals influence actions and behaviors. Among the options provided, the question closely related to goal theory would be: 'What makes hospital workers motivated to work harder?' This relates to goal theory since it involves the study of how setting specific, challenging, and attainable goals can motivate individuals to enhance their performance in the workplace. Goal theory is often applied in organizational settings to improve employee motivation, performance, and job satisfaction. Other domains such as clinical psychology, human factors psychology, and the quest for happiness also intersect with goal theory through the motivation lens, but with different emphases.
For instance, a human factors psychologist would likely be concerned with designing workstations that promote efficient and comfortable interactions between humans and their tasks, which might include aspects such as the height of the chair (option a), rather than the other distractions mentioned. Understanding what motivates employees can also lead to insights into job satisfaction, which falls under the domain of organizational psychology. Hence, goal theory has a broad application across various psychological specializations that deal with human motivation and behavior.